Elastic yarn tensioning and clamping mechanism for knitting machines



Feb. 6, 1968 c. R. ALLRED 3,367,146

ELASTIC YARN TENSIONING AND CLAMPING MECHANISM FOR KNITTING MACHINES Filed June 28, 1965 2 Sheets-Sheet 1 CHARLES Ri a 512 55 &

ATTORNEYS Feb. 6, 1968 c. R. ALLRED 3,367,145

ELASTIC YARN TENSIONING AND CLAMPING MECHANISM FOR KNITTING MACHINES 2 Sheets-Sheet 2 Filed June 28, 1965 INVENTOR. CHARLES 12. ALLEE-b ATTORNEYS I United States Patent Ofiiiee 3,367,146 Patented Feb. 6, 1968 3,367,146 ELASTIC YARN TENSIONING AND CLAMPING MECHANISM FOR KNITTING MACHINES Charles R. Alli-ed, Burlington, N .C., assignor to Alamance Industries, 1110., Burlington, N.C., a corporation of North Caroiina Filed June 28, 1965, Ser. No. 467,589 5 Claims. (Cl. 66I34) ABSTRACT GF THE DISCLUSURE The clamp for the elastic yarn cooperates with the suction tensioning means and yarn cutting means of the knitting machine to clamp the elastic yarn before it is cut and maintain it under uniform tension while the elastic yarn is not being knit, and to maintain the uniform tension on the yarn as it is again knit. The clamp is supported on the suction means and is operated through pattern controls of the knitting machine to operate at the proper times during the knitting of support hosiery and the like.

This invention relates to an elastic yarn tensioning and clamping mechanism for circular hosiery knitting machines of the type having means for cutting the yarns closely adjacent the needle circle as they are removed from and returned to knitting position and including suction means adapted to remove the cut terminal end portions of yarns returned to knitting position and for tensioning the ends of the yarns as they are removed from and returned to knitting position.

In the knitting of ladies nylon hosiery, great savings have been realized by providing means on the machines for cutting the ends of both the ingoing and outgoing yarns close to the needle circle during the operation of the knitting machine, thereby eliminating the separate operation of cutting the long yarn ends during the inspection of the hosiery. At the present time almost all fine gauge ladies seamless hosiery machines have cutters positioned closely adjacent the needle circle and they have some type of mechanical clamp that works in conjunction with a suction tube to hold the ends of the yarns as they are removed from and returned to knitting position. These presently known types of clamp and cutters operate etficiently when inelastic yarns are being knit, however, they are not adapted to properly cut and clamp an elastic yarn and maintain it under the proper tension while it is removed from knitting position. For example, in the knitting of support type hosiery, it is customary to feed an elastic yarn under a predetermined tension during the rotary knit portions of the leg and foot and to remove the elastic yarn from knitting poistion so that a different type of yarn may be knit in the reciprocatorily knit heel and toe pockets. The known types of cutting and clamping devices either fail to clamp and hold the elastic yarn or permit the tension to be reduced while it is removed from knitting position, such as during the knitting of the heel pocket. If the elastic yarn end is not properly clamped when the elastic yarn feed finger is moved to an inactive position, the elastic yarn will not be properly fed to the needles when the elastic yarn feed finger is returned to active position. If the tension of the elastic yarn is reduced while the elastic yarn feed finger is in an inactive position, the elastic yarn will then be initially fed to the needles in a partially relaxed condition, when the elastic yarn feed finger is returned to active position.

With the foregoing in mind, it is a primary object of the present invention to provide means for feeding an elastic yarn to a circular knitting machine under a predetermined tension and means for clamping and holding the elastic yarn to maintain the predetermined tension therein from the time it is removed from knitting position until after it is again returned to knitting position.

It is a more specific object of the present invention to provide elastic yarn clamping means that is carried by the suction tube and operated in timed relationship to operation of the elastic yarn feeding finger to clamp the elastic yarn before it is cut and to hold it under tension while the elastic yarn feed finger remains in an inactive position.

It is a further object of the present invetnion to provide an elastic clamping means of the type described that may be utilized on either a single-feed circular knitting machine or a multi-feed circular knitting machine.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds, when taken in connection with the accompanying drawings, in which FIGURE 1 is a fragmentary perspective view of the upper portion of a circular knitting machine, illustrating the manner in which the elastic yarn is fed thereto, and schematically illustrating a cross-sectional portion of the pattern control means for operating the elastic yarn clamp;

FIGURE 2 is an enlarged plan view of the head portion of the circular knitting machine shown in FIGURE 1;

FIGURE 3 is an enlarged vertical sectional view taken substantially along the line 3-3 in FIGURE 2 and illustrating the manner in which the elastic yarn clamp is carried by the suction tube;

FIGURE 4 is a horizontal sectional view looking downwardly on the dial of the knitting machine, being taken substantially along the line 44 in FIGURE 3;

FIGURE 5 is a fragmentary front elevational view, with parts broken away, of the lower end of the suction tube with the elastic yarn clamp attached thereto; and

FIGURE 6 is a vertical sectional view through the elastic yarn clamp and suction tube, being taken substantially along the line 6-6 in FIGURE 5.

The elastic yarn tensioning and clamping mechanism of the present invention is particularly useful in the knitting of ladies support hosiery wherein an elastic yarn, such as covered spandex, is knit on every other needle in alternate courses while an inelastic yarn, such as nylon, is knit on every needle of the intervening courses throughout the rotary knit portions of the leg and foot. This type of support hosiery can most economically be knit on a twofeed circular knitting machine with the elastic yarn being fed to the needles through an elastic yarn feed finger at the auxiliary knitting station and the inelastic nylon yarn being fed through a feed finger at the main knitting station and wherein the heel and toe pockets are knit in a singlefeed manner at the main knitting station, usually with an inelastic yarn of heavier denier than the inelastic yarn used in the leg and foot portions.

anism is disclosed in association with a two-feed circular knitting machine of the type manufactured by Textile Machine Works and known as their Reading Mark III. This type of machine is conventionally supplied with a yarn clamping and severing mechanism of the type shown in the James D. Moyer US. Patent No. 3,097,512, issued July 16, 1963. However, it is to be understood that the present elastic yarn tensioning and clamping mechanism may also be utilized with other types of single or multifeed circular knitting machines.

Referring to the drawings, the conventional parts of the knitting machine will be described first and then the present elastic yarn tensioning and clamping mechanism will be described in association therewith. The knitting machine is provided with the usual rotary needle cylinder (FIGURE 1) that supports a circle of latch needles N (FIGURE 3) for vertical movement. A latch ring 12 is suitably supported in spaced relationship above the usual sinker cap 13. A dial mechanism, broadly indicated at 14 and shown in dash-dot lines in FIGURE 3, is supported within the needle circle and includes a nonrotating dial cap 15 (FIGURE 4) thatsupports the cutting and clamping mechanism to be presently described.

Transfer bits, not shown, are mounted for radial movement in the rotating lower portion of the dial in a conventional manner and an annulus 16 (having sharp-edged peripheral teeth) is supported beneath the dial cap 15 for rotary movement with rotation of the needle cylinder 10. The annulus 16 is rotated (in a counterclockwise direction in FIGURE 4) by means of the usual driving mechanism, including a vertically disposed drive shaft 20 (FIG- URE 4), a horizontally disposed drive shaft 21 (FIGURE 3) and suitable bevel gears, not shown, which are disposed in a gear housing 23 that is in turn suitably supported on the latch ring 12.

Yarn feed fingers are suitably supported for movement into and out of knitting position to thereby feed yarns to the needles at spaced positions around the latch ring 12. As shown in FIGURES 2 and 4, the feed fingers at the main knitting station are collectively indicated at while the feed fingers at the auxiliary knitting station are collectively indicated at 31. A yarn clamp lever 32 is spaced from the main yarn feed fingers 30 (FIGURE 4) and is pivotally supported intermediate its ends as at 33. The lower end of a suction tube 34 is provided with an outwardly flared foot portion 35 which is spaced closely above the upper surface of the dial cap 15 so that yarn may pass therebetween, in a manner to be presently described.

A bracket 36 pivotally supports one end of a cutter control arm 37 which has a cutter blade 38 supported at its other end. The lower end of the cutter blade 38 may remain at all times in a lowered operative position in engagement with the teeth on the outer periphery of the annulus 16 as it rotates thereby. The lower end of a control link 39 is connected to a medial portion of the cutter control arm 37 and the upper end is connected to pattern control means, not shown, that may be operated in timed relationship to movement of the yarn feed fingers 30 at the main knitting station to at times hold the cutter blade 38 in a raised inoperative position out of engagement with the annulus 16 and then lower the cutter blade to the operative position during a yarn change.

Following the yarn feed fingers 31, at the auxiliary knitting station, a yarn clamp lever 42 is pivotally supported as at 43 and overlies the dial cap 15. The lower end of a suction tube 44 is disposed in closely spaced relationship above the upper surface of, the dial cap 15. This suction tube 44 normally has an outwardly flared foot portion like the one shown on the suction tube 34, heretofore described, however, in the present instance the foot portion is not used so that the elastic yarn clamping member of the present invention may be supported thereon, in a manner to be presently described.

A bracket 46 pivotally supports one end of a cutte control arm 47 that has a cutter blade 48 supported at its other end. The cutter blade 48 may remain in the lowered operative position at all times. However a control link 49 is provided so that the cutter blade 48 may be lowered into engagement with the teeth on the outer periphery of the annulus 16 only during the yarn change.

Opposite ends of an intermediate lever 50 extend 'below the yarn clamp levers 32, 42 (FIGURE 4) and the medial portion of the lever St) is pivotally supported, as at 51. A tension spring 52 is connected between the yarn clamp lever 42 and an upstanding spring perch on the medial portion of the intermediate lever 50. The spring 52 normally biases the lower surfaces of the clamp levers 32, 42 into engagement with the upper surface of the dial cap 15 so that the yarns extending therebeneath are clamped against the upper surface of the dial cap 15.

The lower end of a piston plunger 53, shown in dotted lines in FIGURE 4, engages one end of the yarn clamp lever 32. The piston plunger 53 is at times forced downwardly by air pressure in an air cylinder 54 (FIGURES 1 and 2) that has one end of an air pressure line 55 connected thereto. The other end of the air pressure line 55 is connected to a manifold housing block 56, into which air under pressure is directed in timed relationship to operation of the yarn feed fingers 30, 31.

As shown in FIGURE 2, the upper ends of the suction tubes 34, 44 are curved and extend into a receptacle 57 for receiving and collecting the waste lengths of yarn that are drawn upwardly through the suction tubes 34, 44. Air pressure lines 60, 61 are joined at one end to the respective suction tubes 34, 44 and their other ends are suitably connected to the air pressure manifold block 56. When air pressure is introduced into these lines 60, 61, suction currents are produced at the lower ends of the suction tubes 34, 44 to draw the ends of the cut inelastic yarns up into the suction tubes as soon as they are cut closely adjacent the needle circle by the respective cutter blades 38, 48.

The conventional clamping levers 32, 42, suction tubes 34, 44, and cutting blades 38, 43 operate satisfactorily when feeding and knitting inelastic yarns at the main and auxiliary knitting stations 30, 31. For example, when one of the inelastic yarn feed fingers 30, 31 is raised to the inactive position at either the main or auxiliary knitting station, air under pressure is introduced into the manifold block 56 and the air pressure lines 55, 60, 61 to thereby create suction in both of the suction tubes 34, 44 and at the same time depress the plunger 53 (FIGURE 4) to thus raise both of the clamping levers 32, 42. The yarn will be engaged by the teeth of the annulus 16 at a point closely adjacent the last active needle to be carried around the needle circle so that it extends across the dial cap 15 and beneath the corresponding suction tube and clamp lever as it approaches the corresponding cutter blade following the feed station at which the yarn was moved to inactive position. As the inactive yarn is carried beneath the cutter blade by the annulus, it will be cut closely adjacent the needles and the free end will be drawn up into the corresponding suction tubes 34, 44 where it is held by the suction currents until the clamping levers 32, 42 are released and pulled downwardly by the spring 52 into resilient clamping engagement therewith.

When a yarn feed finger is lowered to an active position, suction is created in the tubes and the clamping levers are raised as the yarn is picked up by the first active needle and moved into engagement with the teeth on the outer periphery of the annulus 16. As the yarn is carried toward the cutter blade by the annulus 16, the leading terminal end portion of the yarn is maintained under tension by the suction. As soon as the yarn is cut closely adjacent the needle circle by the cutter blade, the waste end of yarn (extending from the cutter blade and up into the suction tube) is drawn up through the corresponding suction tube and deposited in the receptacle 57.

While this conventional clamp and cutter mechanism works satisfactorily with inelastic yarns, it will not operate satisfactorily with elastic yarns which are maintained in a stretched and tensioned condition. With the conventional mechanism there is nothing to hold the stretched elastic yarn as it is cut so that it will immediately snap back or retract to, and many times through, the yarn feed finger.

In accordance with the present invention, the elastic yarn, indicated at E, is fed through one of the feed fingers 31 at the auxiliary knitting station (FIGURES 3 and 4) and elastic yarn clamping means, broadly indicated at 60, is supported on the lower end of the suction tube 44. In a manner to be presently described, the clamping means 60 operates to clampingly hold the elastic yarn and prevent it from snapping back through the yarn feed finger when it is cut by the cutter blade 48 (FIGURE 4). Also, in accordance with the present invention, an improved tensioning device is provided to maintain uniform tension on the elastic yarn while it is in both the active and inactive positions.

As shown in FIGURE 1, the elastic yarn E is withdrawn from a supply spool 65, passes upwardly through a guide eye 66, and around a tension reel 67 that is supported for rotation on a disk 68 which is in turn suitably supported on the yarn rack stand 69 by a bracket 70. The tension reel 67 may have varying amounts of braking force applied thereto by rotating an adjustment knob 71 to thereby increase or decrease the drag or tension on the elastic yarn as it proceeds to the knitting machine from the tension reel 67, The elastic yarn passes over a guide roller 72 and is then led downwardly to and through the elastic yarn feed finger 31 (FIGURE 3) at the auxiliary knitting station.

In FIGURE 3, the end of the elastic yarn E is shown in clamped position, being held by the elastic yarn clamping means 60. In FIGURE 4, the elastic yarn feed finger has been raised to inoperative position and the elastic yarn E has been carried around by the annulus 16 to a position where it is ready to be cut by the cutter blade 48. The elastic yarn E is drawn across the upper surface of the dial 15, beneath the lower end of the suction tube 44, beneath the raised clamp lever 42, and has just been clamped by the clamp means 60. The elastic yarn clamping means 60 is carried by and fixed on the side of the suction tube 44 which faces the yarn feed fingers 31, at the auxiliary knitting station. Thus, as shown in FIGURE 4, the elastic yarn clamping means 60 is positioned between the elastic yarn feed finger 31 and the cutting blade 48 and is carried by the lower end of the suction tube 44, which is positioned in alignment between the yarn feed fingers 31 and the cutter blade 48.

The elastic yarn clamping means 60 includes a substantially vertically disposed slide bracket 73 that is suitably secured, as by soldering, to the lower end of the suction tube 44. The slide bracket 73 is provided with a channel or groove in which the lower end of a clamp slide 74 is supported for vertical sliding movement. A cover plate 75 is held in position on the front face of the slide bracket 73 by nuts 76 which are threaded onto the outer ends of guide pins 77, that extend through guide slots 78 in the clamp slide 74 and are fixedly secured at their inner ends in the slide bracket 73 (FIGURE 6). One side of the lower end of the clamp slide 74 is cut away to form a clamp foot 80 on the lower end of the clamp slide 74 (FIGURE 5).

When the clamp slide 74 is moved to its lowermost position, shown in FIGURE 5, the lower surface of the clamp foot 80 engages the upper surface of the dial cap and the upper edge of the clamp foot 80 is positioned in spaced relation below the lower end of the slide bracket 73 andplate 75 to define an elastic yarn receiving gap between the clamp foot 80 and the lower end of the slide bracket 73 and cover plate 75. With the clamp slide 74 in this position, the clamp member 60 is in an open or yarn receiving position.

When the clamp slide 74 is raised, in a manner to be presently described, the clamp foot will.move up into the guide slot in the slide bracket 73 to draw the elastic yarn up into and between the cover plate 75 and the lower end of the slide bracket 73 to thereby clamp the elastic yarn therein.

The upper end of the clamp slide 74 (FIGURE 3) is provided with a threaded extension 84 having self-locking adjustment nuts 85 and 86 supported thereon for adjustment relative to each other. The clamp slide 74 is normally urged upwardly to the closed or clamping position, shown in FIGURE 3, by means of a tension spring 90, the lower end of which is suitably secured to a spring perch 91 on the clamp slide 74 and the upper end of which is suitably secured on a spring perch bracket 92 that is in turn supported on the gear housing 23.

Pattern control means is operatively associated with the elastic yarn clamping means 60' and includes a composite linkage that is connected at one end to the threaded extension 84 of the clamp slide 74. The composite linkage comprises a substantially horizontally disposed first lever 94 which is penetrated at one end by the threaded portion 84 of the clamp slide 74 and is pivotally supported as at 95 adjacent its other end on a fixed support bracket 96. A second substantially horizontally disposed lever 97 is pivotally supported adjacent one end as at 98 on the support bracket 96 and its other end is suitably'connected to the upper end of a tension spring 99*.

The horizontally disposed levers 94, 97 are operatively connected at their corresponding inner ends, as at 100*. When downward movement is imparted to the outer end of the lever 97, downward movement will also be imparted to the outer end of the lever 94 so that it will engage the lower adjustment nut 86 and move the clamp slide 74 downwardly, thereby moving the clamping means 60 to the open position. 1

The lower end of the tension spring 99 is suitably connected to the upper end of a Bowden wire cable 101, the lower end of which is suitably connected to the lower end of a cam lever 102 (FIGURE 1). The cam lever 102 is pivotally supported intermediate its ends and its upper end is adapted to engage the periphery of a pattern drum 103 which is rotated in timed relationship to operation of the machine, in a well-known manner. Spaced apart cams 104, 105 (FIGURE 1) are provided on the pattern drum 103 and in alignment with the cam lever 102. When it is desirable to discontinue knitting with the elastic yarn E, as during the knitting of the heel and toe pockets of a ladies support stocking, the respective cams 104, 105 successively engage the cam lever 102 to thereby move the elastic yarn clamping means 60 to its open or yarn receiving position.

The operation of the present yarn tensioning and clamping means will now be described, assuming that the knitting machine is forming the lower leg portion of the leg of a support stocking and approaching the heel pocket. At this time, the elastic yarn E is being fed to the needles through one of the yarn feed fingers 31 at the auxiliary knitting station and the tension reel 67 is stretching the elastic yarn E the desired amount. The main body yarn of inelastic nylon is being fed to the needles through one of the yarn feed fingers 30 at the main knitting station.

During the knitting of the last full course of the leg, before beginning the reciprocatorily knit heel pocket, the body yarn feed finger at the main knitting station 30 is raised to inactive position after a heel yarn feed finger has move into active position to form a yarn overlap and begin feeding a heavier denier yarn for knitting the heel pocket at the main station 30 only. Also, during the knitting of this last full course of the leg portion, the elastic yarn feed finger at the auxiliary knitting station 31 is raised to inactive position. Just before the yarn change, air under pressure is admitted to the manifold block 56 to pass through lines 55, 60, 61 (FIGURE 2) to thereby move the piston plunger 53 (FIGURE 4) downwardly and raise the clamp levers 32, 42 and simultaneously create suction in the suction tubes 34, 44. During the yarn change at the main knitting station, the cutter 38, suction tube 34 and clamp lever 32 operate in the conventional manner so that the end of the body yarn removed from knitting action and the end of the heavy heel yarn are each cut closely adjacent the needle circle.

As the elastic yarn feed finger 31 at the auxiliary station 31 (FIGURE 4) is raised to the inactive position, the cam 104 on the pattern drum 103 will engage the lever 102 (FIGURE 1) and cause the clamping means 60 to move to the open yarn receiving position shown in FIGURE 5. The last needle to take the elastic yarn will cause it to engage the teeth on the annulus 16 and the yarn will be carried around the needle circle and drawn across the dial cap 15. As the elastic yarn E approaches the cutter blade 48, as shown in FIGURE 4, the elastic yarn E will be stretched beneath the suction tube 44 and over the foot portion 80 of the clamp slide 74, beneath the raised clamp lever 42, and back through the raised elastic yarn finger. At this point, the heel cam 104 will move from beneath the lever 102 so that the spring 90 (FIGURE 3) immediately moves the cutter slide clamp 74 upwardly to clamp the elastic yarn E, just before it is cut by the cutter blade 48. When the stretched elastic yarn reaches the cutter blade 48 and is severed, it will snap back to the clamping means 60 only so that the tension in the elastic yarn is maintained between the clamping means 60 and the tension reel 67. The clamping means 60 is maintained in this closed position until the knitting of the toe pocket begins and the elastic yarn is held under tension, as shown in FIGURE 3 until after completion of the knitting of the heel pocket, when the elastic yarn E is again moved to the knitting position.

When the elastic feed finger is again lowered to knitting position to start feeding the elastic yarn E, at the completion of the knitting of the heel pocket, it is not necessary to actuate the elastic clamping means 60. The first active needle will pick up the elastic yarn E so that it will be carried around the needle circle by the teeth on the annulus 16 to the cutter blade 48. As the elastic yarn is cut closely adjacent the needle circle, the free end of the waste end of the elastic yarn, extending from the clamping means 60 to the cutter blade 48 will be drawn up inside of the suction tube 44 where it will remain until the clamping means 60 is again moved to the open position. At the beginning of the toe pocket, the cam 105 on the pattern drum 103- (FIGURE 1) will engage the. lever 102 to move the clamping means 60 to the open position to thereby release the waste end of the elastic yarn so that it may be drawn up and into the receptacle 57. The clamping means 60 is then in open position to receive and clamp the elastic yarn as it is removed to knit the toe pocket of the heavier denier body yarn at the main knittingstation.

Thus, the elastic yarn tensioning wheel 67 maintains a constant tension on the elastic yarn, and the elastic yarn clamping means 60 positively holds the elastic yarn and maintains the tension in the elastic yarn while it is not being fed, such as during the knitting of the heel pocket. With these means of the present invention, the elastic yarn E can be moved from active knitting position to inactive position and then back to the active knitting position while maintaining a substantially uniform and constant tension on the elastic yarn E.

In the drawings and specification there has 'been set forth a preferred embodiment of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. In a circular knitting machine having a rotary cylinder with a circle of needles carried thereby, a dial cap supported within the needle circle, yarn feeding fingers including at least one elastic yarn feed finger movable between active and inactive positions relative to the needles, yarn severing means spaced from said yarn feed fingers and carried by said dial cap for severing yarns closely adjacent the needle circle, and suction means positioned closely adjacent the upper surface of said dial cap and aligned between said yarn severing means and said yarn feeding fingers, said suction means including a substantially vertically disposed tube having an open lower end, a yarn clamping lever positioned between said yarn feeding fingers and said suction means for clamping engagement with the yarns from the other feeding fingers, the yarn from an inactive feed finger being moved beneath said suction means as it approaches said yarn severing means, the combination therewith of (a) elastic yarn tensioning means for maintaining a constant tension on the elastic yarn fed to the needles through the elastic yarn feed finger,

(b) elastic yarn clamping means carried by said suetion means, said clamping means being positioned on the side of said suction means facing said elastic yarn feed finger, said clamping means being movable between an open yarn receiving position and a closed clamping position, said elastic yarn clamping means including a slide bracket having a lower end disposed at substantially the same level as the lower end of said tube, a clamp slide supported for verticalmovement in said slide bracket and having a clamp foot on its lower end, said clamp foot being disposed in a horizontal position and movable into engagement with said dial cap and in spaced relation below the lower end of said slide bracket to define an elastic yarn receiving gap between said clamp foot and the lower end of said slide bracket, said clamp foot being movable upwardly into the lower end of said slide bracket to clamp and hold the elastic yarn, and

(0) pattern control means operatively associated with said elastic yarn clamping means for opening said clamping means to receive the elastic yarn therein as it moves beneath said suction means, and said pattern control means operating to close said clamping means just prior to operation of said yarn severing means to hold the elastic yarn under said predetermined tension after it is severed closely adjacent the needle circle and while said elastic yarn feed finger remains in the inactive position.

2. -In a knitting machine according to claim 1 including resilient means connected to said clamp slide and normally urging the same upwardly whereby said clamp foot is disposed within the lower end of said slide bracket so that said clamping means is in the closed position.

3. In a knitting machine according to claim 1 wherein said pattern control means is connected to the upper end of said clamp slide and is operative to move the same downwardly whereby said clamp foot is disposed in spaced relation below the lower end of said slide bracket so that said clamping means is in the open position.

4. In a knitting machine according to claim 3 wherein said pattern control means includes a composite linkage supported on the machine and connected at one end to the upper end of said clamp slide, a spring connected at one end to the other end of said composite linkage, a Bowden wire connected at one end to the other end of said spring, a cam lever connected at one end to the other end of said Bowden wire, and a pattern drum having cams for engagement by the other end of said cam lever to impart downward movement to said clamp slide and move said clamping means to the open position.

5. In a knitting machine according to claim 4 including a fixed support bracket and wherein said composite 9 10 linkage includes a first substantially horizontally disposed References Cited lever connected at one end to the upper end of said clamp UNITED STATES PATENTS slide and being pivotally supported adjacent its other end 2,432,110 12/1947 [Lambach 66*145 on said support bracket, a second substantially honzonr 3,097,512 7/1963 Mayer 66 145 XR tally disposed lever pivotally connected at one end to the 3 257 829 6/1966 Parthum other end of said first lever, pivotally supported adjacent u said one end on said support bracket, and being con- FOREIGN PATENTS nected at its other end to said spring so that said compos- 944,934 12/ 1963 Great Britain.

ite linkage imparts downward movement to said clamp slide with downward movement of said spring. 10 ROBERT MACKEY Pr'mary Emmmer- 

